The present invention relates to an image processing device, an imaging device, an image processing method, and the like.
It has become possible to capture a high-resolution image along with an increase in the number of pixels of image sensors. However, when the pixel size is merely reduced to increase the number of pixels, the light intensity per pixel decreases, and the S/N ratio deteriorates, for example. Specifically, good image quality is not necessarily obtained by merely reducing the pixel size. A pixel-shift imaging method has been proposed to deal with such a problem (see JP-A-11-18097 and JP-A-2005-143031, for example). According to the pixel-shift imaging method, since only the sampling interval can be reduced to be smaller than the pixel size while maintaining the pixel size, it is possible to obtain a high-resolution image without causing a deterioration in S/N ratio as compared with the case of capturing an image using an image sensor having an identical pixel size without performing a pixel shift.
JP-A-11-18097 discloses a method that captures an image while performing a pixel shift (⅔ pixel pitch) three times in the horizontal scan direction and three times in the vertical scan direction (nine times in total) so that the resulting color data has the same arrangement as that of the original color data. JP-A-2005-143031 discloses a method that captures an image while performing a pixel shift once in the vertical scan direction (1 pixel pitch) and four times in the horizontal scan direction (½ pixel pitch) (five times in total) to acquire color data having a honeycomb-like arrangement. A method that captures an image while performing a pixel shift (½ pixel pitch) four times in the horizontal scan direction and four times in the vertical scan direction (sixteen times in total), and a method that captures an image while performing a pixel shift (⅓ pixel pitch) six times in the horizontal direction and six times in the vertical direction (thirty-six times in total), have also been known.